The 7-foot-1, 325-pound O'Neal, who threw out the first pitch before the Cardinals' game against the Reds on Tuesday night, is in town to film an episode for his new reality television show, which will debut this fall.
O'Neal will challenge Cardinals slugger Albert Pujols to a baseball competition on Thursday night at T.R. Hughes Stadium in O'Fallon, Mo., and the 6,000-seat stadium ran out of the free tickets in a matter of minutes.
But on Tuesday, he was getting batting tips from Ryan Ludwick and got a tour of the Cardinals locker room from Pujols. He signed several baseballs and took pictures with most of St. Louis' players.
"It's crazy because obviously he's huge, but he runs well," said pitcher Blake Hawksworth. "He runs the floor. He does a lot of the little stuff that normal big guys don't do. I appreciate him more now after seeing how massive he is.
"I bought his first rap CD when I was a kid, 'Shaq Diesel.' He's the best."
After touring the Cardinals' clubhouse and receiving a customized No. 33 jersey from Pujols, O'Neal watched St. Louis take batting practice as several Reds and Cardinals players came to introduce themselves.
"We got some big guys on our team," said Cardinals infielder Joe Thurston. "But he just makes everybody look little."
Shortstop Brendan Ryan, a lifelong Lakers fan who lives in Los Angeles during the offseason, shook hands and spoke with O'Neal in between his rounds of batting practice.
"I just wanted to say hi and introduce myself," Ryan said. "I told him I grew up and still live 10-15 minutes from the Staples Center, right down Olympic, and I'd go see him play all the time. I was a big fan.
"I tried to go deep for him several times and I hit the wall a couple of times. It was humbling but still pretty funny. I asked him if he'd come back to L.A. for another year, but it didn't sound like that was in the works."
Several sound and camera operators followed O'Neal's every move, as did the show's producers and directors.
"I've never seen an entourage like that, it was nuts," Ryan said. "But he's Shaq. It's pretty funny, it's kind of a zoo."
O'Neal spoke to the Busch Stadium crowd after throwing out the first pitch and publicly challenged Pujols to a home run derby on Thursday night. As the crowd cheered, Pujols smiled.
"Good luck," Pujols said.
B.J. Rains is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.